Engineer Presentation. Efficiency - GAS. Clamshell Heat Exchanger 80% Efficient. Typical two furnace unit. 400 °F. 1700 °F. Typical two furnace unit. 70 °F. 120 °F. 20 °F. 80 % Efficient. 75% Efficient. Air Stratification - Typical Heat Exchanger. 10-15 °F Δ T. Heat Exchanger.
10-15 °F ΔT
300 MBH input
??? °F ΔT
Single Stage VS Modulation
The minimum turn down must be set to ensure condensing in the secondary heat exchanger or both heat exchangers must be made out of stainless steel.
The Power Venter/Draft Inducer’s airflow directly affects the gas to air ratio at the burner. The ratio must be set to keep Air Free CO below 400 PPM.
Hot Water Coil
VFD & Transformer
This recovered waste heat increases the efficiency by 1+%